The vacuum-assisted brake pump is mounted to the rear of the right side (rear bank) cylinder head. To remove it, first loosen the left front tire lug nuts, then raise the vehicle and support it securely on a pair of jack stands. Disconnect the negative battery cable. Remove the left front wheel, and then remove the inner fender liner. Remove engine lower splash shield and drain radiator coolant. On Highlander models, remove windshield wiper arms and motor linkage then remove cowl vent tray. Remove air filter housing. On Highlander models, remove throttle body. Disconnect transaxle control cable from top of transaxle then unclip cable from bracket. Disconnect breather hose and PCV hose. Disconnect heater hoses from coolant outlet pipe. Release hose clamps and take off hoses from vacuum pump. Disconnect main engine wiring connectors, then harness retainers and lift harness away from vacuum pump.Remove mounting bolts of vacuum pump and slide out vacuum pump from rear of right side (rear bank) cylinder head. Should there be any oil leaks or damaged o-ring, replacement must be done for the vacuum pump assembly.To install: Apply a thin coat of engine oil to O-rings of vacuum pump and inside hole in cylinder head.Align vacuum pump coupling with grooves at end of camshaft and insert the pump.Put in place mounting bolts and tighten them according to torque.Remainder of installation is reverse order of removal.The brake power assisted switch is mounted onto the front face of
Brake Booster.Remove cowl panel.Disconnect electrical connector from switch; note how connector end points.Carefully pry warning switch out of grommet in brake booster making sure not to damage grommet.Install brake power assisted switch into booster ensuring that connector points in right direction.If warning switch is installed on upper half of booster, electrical connector end should point at 11 o'clock position.If switch is installed on lower half of booster, connector end should point at 5 o'clock position.